Group 4 metal-based metal–organic frameworks (M^IV-MOFs), including Ti-, Zr-, and Hf-based MOFs, are one of the most attractive classes of MOF materials owing to their superior chemical stability and structural tunability. Despite being a relatively new field, M^IV-MOFs have attracted significant research attention in the past few years, leading to exciting advances in syntheses and applications. In this outlook, we start with a brief overview of the history and current status of M^IV-MOFs, emphasizing the challenges encountered in their syntheses. The unique properties of M^IV-MOFs are discussed, including their high chemical stability and strong tolerance toward defects. Particular emphasis is placed on defect engineering in Zr-MOFs which offers additional routes to tailor their functions. Photocatalysis of M^IV-MOF is introduced as a representative example of their emerging applications. Finally, we conclude with the perspective of new opportunities in synthesis and defect engineering.

中文翻译：

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具有第4组金属的稳定金属-有机框架：现状和趋势

第4组金属基金属有机框架（M ^IV -MOF），包括Ti-，Zr-和Hf-基MOF，由于其优异的化学稳定性和结构可调性，成为最吸引人的MOF材料类别之一。尽管是相对较新的领域，但在过去的几年中，M ^IV -MOF吸引了重要的研究关注，从而在合成和应用方面取得了令人激动的进展。在这种前景下，我们首先简要介绍M ^IV -MOF的历史和现状，着重介绍其合成过程中遇到的挑战。M ^IV的独特特性讨论了MOF，包括其高化学稳定性和对缺陷的强耐受性。Zr-MOF的缺陷工程特别受重视，它提供了其他途径来调整其功能。介绍了M ^IV -MOF的光催化作为其新兴应用的代表性实例。最后，我们以综合和缺陷工程中的新机会的观点作为结束。